%intro
\section{Introduction}
The \textit{Internet of Things} (IoT) has been a popular research topic in recent years and still has a large momentum that can be seen in present research projects. The core concept of the future Internet of Things is the integration of physical objects into an information network. Information about the objects should be represented in the Internet and direct interaction between physical objects should be possible. 
The term \textit{Internet of Things} was first mentioned in 2001 in the paper that presents the Electronic Product Code~\cite{brock2001electronic} (EPC), which is a naming scheme for physical objects. It describes a naming scheme which in turn provides an address space that is large enough to enumerate all physical objects, starting from a simple item over containers to pallets and vehicles used for transportation. The IoT first gained widespread attention when the Auto-ID center presented their vision of the EPC network~\cite{ashton2003introducing} in 2003, which is used to automatically identify the flow of goods within supply chains.

The central aspect of a supply chain is to know where parts are currently and when they are needed at a specific location (which might be another factory that requires these intermediate products to manufacture other products). The Internet of Things allows to optimize these process chains and, by providing real-time data, enables timely business intelligence that offers actual data to business analysis tools.

In the following years the term has been broadened to the concept of a seamless integration of physical objects into the internet through virtual representation. There are several different view points on the Internet of Things as outlined in Figure~\ref{fig:iot} taken from~\cite{atzori2010internet}. The concepts used and required to build an Internet of Things come either from a \textit{things}-centered point of view, an Internet- and communication-oriented approach or focused on the semantic aspects of the IoT.

\begin{figure}[h]
	\centering
		\includegraphics[width=0.75\columnwidth]{res/iot}
	\caption{Aspects of the Internet of things \cite{atzori2010internet}}
	\label{fig:iot}
\end{figure}

This includes tagging physical objects with an electronic identifier like RFID. Wireless communication technologies on resource constrained devices allow a large-scale deployment of electronic identifiers, sensors and actuators. However, the integration into the Internet requires an uniform addressing scheme allowing to identify devices and furthermore interoperable technologies that allow information exchange between physical objects and the Internet.

Technologies like RFID, NFC and advances in wireless communication and integration of automation systems subsuming sensor and actuator devices contributed to the research in the Internet of Things and a realization of its vision is becoming more feasible.

There are several possible use cases~\cite{atzori2010internet} for the Internet of Things:
\begin{itemize}
\item \textbf{Transportation and logistics}: The location of goods or trucks can be provided in real time to a smart supply chain management system. 
\item \textbf{Healthcare}: Sensors can detect emergency cases and send an alert to EMTs.
\item \textbf{Smart environments}: Smart homes automatically control the room temperature and optimize the energy consumption. Assisted living can ease the daily life of handicapped people.
\item \textbf{Personal and social}: Lost or stolen objects can be located and social networks can be expanded with information provided by physical objects.
\end{itemize} 



